Systems and methods for treating a hollow anatomical structure

Abstract

A catheter includes multiple primary leads to deliver energy for ligating a hollow anatomical structure. Each of the primary leads includes a resistive element located at the working end of the catheter. Separation is maintained between the leads such that each lead can individually receive power. The catheter can include a lumen to accommodate a guide wire or to allow fluid delivery. Energy is applied until the diameter of the hollow anatomical structure is reduced to the point where occlusion is achieved. In one embodiment, a balloon is inflated to place the resistive elements into apposition with a hollow anatomical structure and to occlude the structure before the application of energy. The inflated balloon impairs blood flow and facilitates the infusion of saline, or medication, to the hollow anatomical structure in order to reduce the occurrence of coagulation and to improve the heating of the structure by the catheter.

1. A method for use with a catheter sized for insertion into a human blood vessel, the catheter comprising an elongate shaft having a proximal end and a distal end, a heating coil having a proximal end and a distal end and being located at or near the distal end of the shaft, the heating coil being insulated so as to prevent electrical contact and electrical conduction with tissue, and a temperature sensor located along the coil near and proximal of the distal end of the coil; the method comprising:
 delivering electrical power to the coil while the coil is disposed in a first treatment segment of the blood vessel; 
 monitoring a temperature via the temperature sensor; 
 moving the coil from the first treatment segment; 
 creating partial overlap between the first treatment segment of the blood vessel and a second treatment segment of the blood vessel by sensing a temperature drop via the temperature sensor and determining, based on the temperature drop, that the coil has been moved to the second treatment segment and that the temperature sensor has been moved, wherein the second treatment segment comprises an overlap portion created by the partial overlap between the first and second treatment segments, and a non-overlap portion adjacent to the first treatment segment and the overlap portion; and 
 delivering electrical power to the coil again. 
 
     
     
       2. The method of  claim 1 , further comprising holding the coil stationary in the first treatment segment while delivering electrical power to the coil. 
     
     
       3. The method of  claim 1 , further comprising reducing or deactivating power delivery to the coil after delivering power to the coil while the coil is in the first treatment segment and before delivering power to the coil while the coil is in the second treatment segment. 
     
     
       4. The method of  claim 1 , wherein a portion of the coil is disposed in the first treatment segment while delivering electrical power to the coil in the second treatment segment. 
     
     
       5. The method of  claim 1 , wherein the catheter further comprises a second temperature sensor located on the shaft proximal of the heating coil, and the method further comprises communicating an alert when sensing a temperature drop relative to body temperature at the second temperature sensor. 
     
     
       6. The method of  claim 1 , wherein the heating coil is between about 1 and about 10 centimeters in length. 
     
     
       7. The method of  claim 6 , wherein the overlap is approximately 0.5 centimeters. 
     
     
       8. The method of  claim 1 , wherein delivering power to the coil comprises delivering sufficient power to shrink or occlude the blood vessel. 
     
     
       9. The method of  claim 8 , wherein the method further comprises using a display to symbolically represent which treatment segment is being treated with the coil. 
     
     
       10. The method of  claim 9 , wherein the display comprises an alphanumeric display. 
     
     
       11. The method of  claim 9 , wherein using the display comprises indicating the treatment segment in progress of a total number of treatment segments to be treated. 
     
     
       12. The method of  claim 9 , wherein using the display comprises indicating the number of treatment segments that have been treated. 
     
     
       13. An apparatus comprising:
 a catheter sized for insertion into a human blood vessel, the catheter comprising an elongate shaft having a proximal end and a distal end, a heating coil having a proximal end and a distal end and being located at or near the distal end of the shaft, the heating coil being insulated so as to prevent electrical contact and electrical conduction with tissue, and a temperature sensor located along the coil near and proximal of the distal end of the coil; 
 a display; and 
 a controller electrically connected to the catheter and the display, the controller configured to:
 deliver electrical power to the coil to treat a first treatment segment of the blood vessel; 
 monitor a temperature via the temperature sensor; 
 deliver electrical power to the coil again after sensing a temperature drop via the temperature sensor indicating that the coil has been moved to a second treatment segment of the blood vessel that partially overlaps the first treatment segment and also includes a non-overlapping portion adjacent to the first treatment segment; 
 determine the total number of treatment segments of the blood vessel, including the first and second treatment segments; and 
 provide a signal to the display allowing the display to indicate symbolically which of the treatment segments have been and/or are currently being treated with the coil. 
 
 
     
     
       14. The apparatus of  claim 13 , wherein the controller is further configured to reduce or deactivate power delivery to the coil after delivering power to the coil while the coil is in the first treatment segment and before delivering power to the coil while the coil is in the second treatment segment. 
     
     
       15. The apparatus of  claim 13 , wherein the catheter further comprises a second temperature sensor located on the shaft proximal of the heating coil, and the controller is further configured to communicate an alert when sensing a temperature drop relative to body temperature at the second temperature sensor. 
     
     
       16. The apparatus of  claim 13 , wherein the heating coil is between about 1 and about 10 centimeters in length. 
     
     
       17. The apparatus of  claim 16 , wherein the overlap is approximately 0.5 centimeters. 
     
     
       18. The apparatus of  claim 13 , wherein the display comprises an alphanumeric display. 
     
     
       19. The apparatus of  claim 13 , wherein the display indicates the treatment segment in progress of a total number of treatment segments to be treated. 
     
     
       20. The apparatus of  claim 13 , wherein the display indicates how many treatment segments have been completed. 
     
     
       21. The apparatus of  claim 13 , wherein the heating coil comprises an elongate element that is configured such that, when the elongate element is in a coiled configuration, adjacent turns of the coil are not in electrical contact with one another. 
     
     
       22. The apparatus of  claim 21 , wherein the catheter further comprises an insulating tube surrounding the outside of the coil. 
     
     
       23. An apparatus comprising:
 a catheter sized for insertion into a human blood vessel, the catheter comprising an elongate shaft having a proximal end and a distal end, a heating coil having a proximal end and a distal end and being located at or near the distal end of the shaft, the heating coil being insulated so as to prevent electrical contact and electrical conduction with tissue, and a temperature sensor; 
 a display; and 
 a controller electrically connected to the catheter and the display, the controller configured to:
 indicate on the display a first treatment segment of the blood vessel; 
 deliver electrical power to the coil to treat the first treatment segment of the blood vessel; 
 monitor a temperature via the temperature sensor; 
 distinguish the first treatment segment of the blood vessel from a second treatment segment of the blood vessel that partially overlaps the first treatment segment and also includes a non-overlapping portion adjacent to the first treatment segment; 
 indicate on the display the second treatment segment of the blood vessel; and 
 deliver electrical power to the coil again after sensing a temperature via the temperature sensor and after the coil has been moved to the second treatment segment of the blood vessel. 
 
 
     
     
       24. The apparatus of  claim 23 , wherein the controller is further configured to sense a temperature drop via the temperature sensor indicating that the coil has been moved to the second treatment segment of the blood vessel. 
     
     
       25. The apparatus of  claim 24 , wherein the controller is further configured to distinguish the first treatment segment of the blood vessel from the second treatment segment of the blood vessel by sensing the temperature drop via the temperature sensor indicating that the coil has been moved to the second treatment segment of the blood vessel. 
     
     
       26. The apparatus of  claim 24 , wherein the controller is further configured to distinguish the first treatment segment of the blood vessel from the second treatment segment of the blood vessel by using an indexing system. 
     
     
       27. The apparatus of  claim 24 , wherein the controller is further configured to distinguish the first treatment segment of the blood vessel from the second treatment segment of the blood vessel by using an indexing system that determines the length and number of index steps.